Rotation facts for kids

A sphere rotating around its axis

Rotation is when an object moves in a circle. Think of a spinning top or a planet turning!

If an object is flat (two-dimensional), it spins around a central point. If an object is solid (three-dimensional), it spins around a line called an axis. Imagine a line going right through the middle of the object. When the axis is inside the object, we say the object is spinning on its own.

Sometimes, an object moves in a circle around a point that is outside of it. For example, the Earth moves around the Sun. This kind of circular movement is called an orbit.

How Things Rotate

The Clockwise direction

When something rotates around a point on a flat surface, it can spin in two ways:

• Clockwise: This is the same direction as the hands on a clock move.
• Anticlockwise: This is the opposite direction of clock hands.

Rotation in Airplanes

In flight dynamics, which is how airplanes move, there are three main types of rotation:

• Pitch: This is when the nose of the plane moves up or down.
• Roll: This is when the plane tilts its wings up or down.
• Yaw: This is when the nose of the plane moves left or right.

The word "rotation" is also used when an airplane lifts its nose up to start climbing during takeoff. Fish also use similar movements when they swim through water!

Rotation on Rides

Many fun amusement rides use rotation. A Ferris wheel is a great example. It has a big horizontal axis in the middle that the whole wheel spins around. Each little cabin on the Ferris wheel also rotates, but in the opposite direction, often because of gravity or special gears.

Rotation in Sports

Rotation, often called spin, is super important in many sports. Here are some examples:

• Tennis: Players use topspin (the ball spins forward) and backspin (the ball spins backward) to control where the ball goes.
• Billiards and Pool: Players can make the cue ball spin in different ways, like English, follow, or draw, to change how it hits other balls.
• Baseball: Pitchers throw curve balls by making the ball spin, which makes it curve in the air.
• Cricket: Spin bowling involves making the ball spin to trick the batter.
• Table Tennis: Paddles are designed to help players put lots of spin on the ball when they hit it.

Images for kids

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  Rotational Orbit v Spin

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  Relations between rotation axis, plane of orbit and axial tilt (for Earth).

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  Star trails caused by the Earth's rotation during the camera's long exposure time.

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  The principal axes of rotation in space

See also

In Spanish: Movimiento de rotación para niños